Logo image
Effects of L-arginine-derived nitric oxide synthesis on neuronal activity in nucleus tractus solitarius
Journal article   Peer reviewed

Effects of L-arginine-derived nitric oxide synthesis on neuronal activity in nucleus tractus solitarius

Shengxing Ma, François M Abboud and Robert B Felder
American journal of physiology. Regulatory, integrative and comparative physiology, Vol.268(2), pp.R487-R491
02/01/1995
DOI: 10.1152/ajpregu.1995.268.2.R487
PMID: 7864245

View Online

Abstract

The purpose of these studies was to determine the effects of L-arginine-derived nitric oxide (NO) synthesis on neuronal activity in solitary tract nucleus (NTS) neurons. Single unit activity was recorded extracellularly from medial NTS neurons in Fischer-344 rats in vivo and in vitro. In anesthetized rats with arterial pressure maintained constant, NG-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg iv), an inhibitor of NO synthesis, decreased the discharge rate in 12 of 14 neurons and increased the discharge rate in two. After injection of L-NAME, the slowing of neuronal activity began within 2-5 min, and maximal responses were observed 12-15 min after injection. The decreases in activity were reversed within 12-15 min with L-arginine (30 mg/kg iv) or immediately with nitroglycerin (NTG, 10-30 micrograms/kg iv). In superfused rat brain slices, the discharge rate was reduced by 1 mM L-NAME in seven neurons, increased in two, and unchanged in one. The decreases in discharge rate were reversed by 2 mM L-arginine (4 of 6 neurons) and by 10-30 microM NTG (6 of 7 neurons). The results show that L-arginine-derived NO can affect the spontaneous discharge rate of NTS neurons. We conclude that NO may influence the excitability of NTS neurons involved in central autonomic control.

Details

Metrics

Logo image